I have been using Play 32bit in VE Pro 32bit server on vista 64bit with success. However when I try the same approach in a Win7 partition It comes up with the same problem as you. Blank. When I first used JBridge it came up with the same blank screen but I removed all Scans for VST plugins in VE Pro (except Vienna Inst) and just let JBridge find them and it works a treat in 64bit VE Pro. (as suggested by DG in another post i think).
Seems it's a bit hit and miss as to what systems VE Pro and PLAY will or won't work on.
Have a search on the forum and i'm sure you'll find alot of different things to try
Paul